Former Mines Minister Obert Mpofu has vowed that he will never comment on President Robert Mugabe’s remarks that $15 billion in diamonds revenue vanished in Chiyadzwa.

In brief remarks to Studio 7, Mpofu said, “Look, I will never comment on the issue of diamonds. I am no longer the minister responsible. You must interview the minister of mines. I will never comment on that issue.”

Mpofu is now the Macro Economic Planning and Investment Promotion Minister.

But Mpofu was in charge when the money allegedly disappeared. In 2012, a report released by Partnership Africa Canada said Zimbabwe's Marange fields had seen "the biggest plunder of diamonds since Cecil Rhodes."

Rhodes was the colonial magnate who exploited South Africa's diamonds more than a century ago.

The Canadian non-profit is a member of the Kimberley Process, the international organization set up to stop the trade in so-called "blood diamonds" - diamonds mined to finance conflict.

It alleged that at least $2 billion worth of diamonds had been stolen from the country’s diamond fields and ended up in the pockets of President Mugabe's ruling elite.

But Mpofu at the time rubbished the report calling it “nonsensical” and a work of “detractors.” Responding to questions from parliamentarians today, Mines Minister Walter Chidhakwa said his ministry will investigate the alleged looting of the $15 billion.

At that time, an unidentified lone protestor was also demonstrating outside parliament with a placard and a T-Shirt written, “Where is our Money??”

Opposition parties are calling on President Mugabe to step down saying the alleged pillaging of the funds was done under his watch.

In a press statement, the opposition People’s Democratic Party recommended that “president Mugabe resigns with immediate effect as he has failed the nation as its chief executive.”

The party added that a commission of inquiry must be set up by parliament to investigate the alleged looting which occurred in Chiadzwa and “prosecution of those responsible must follow.”

MDC-T spokesperson, Obert Gutu said the office of the auditor general must be mandated to investigate the case. Gutu said all the money that was looted must be returned to the country.

Kurauone Chihwayi, spokesman of the Welshman Ncube-led MDC also urged Mr. Mugabe to resign for failing to deal with corruption.

In a press statement, Chihwayi said his party is “utterly shocked by revelations of massive looting, corruption and abuse of public funds” adding that “as a party we are convinced that this monstrous oversight is enough grounds for President Robert Mugabe to step down.”